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International Commission on

Radiological Protection

Committee 1 (C1): Radiation Effects

William F. Morgan

Pacific Northwest National Laboratory

USA

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ICRP Mission

Advance for the public benefit the science of

radiological protection by providing recommendations

and guidance on all aspects of protection against

ionizing radiation.

ICRP Structure

Committee 1Effects

Committee 2Doses

Committee 3Medicine

Committee 4Applications

Committee 5Environment

Working PartiesTask Groups

Main Commission Scientific Secretariat

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C1 considers the risk of induction of cancer and heritable disease (stochastic effects) together with the underlying mechanisms of radiation action

C1 also considers the risks, severity and mechanisms of induction of tissue / organ damage and developmental defects (tissue reactions; deterministic effects)

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Fortunate to have a congenial and interactive committee

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C1 Responsibilities & Activity

Continue to monitor data from the atomic bomb survivors (LSS) for both stochastic and deterministic effects, particularly for incidence.

Consider the use of biologically-based dose-response models for assessing effects at low doses (

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C1 Responsibilities / Activity

Follow dosimetry and exposure discussions, DREF, DDREF.

Advances in radiation induced damage recognition, DNA repair, and impact of epigenetic effects.

Long term inflammatory responses and non-cancer effects (CVD, CNS)

Dialogue on heritable effects

Keep abreast of technology

Emphasis on low dose, low dose rate

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CT – the biggest contributor to low dose radiation exposure

Approximately 80 million in the USA this year

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TG 75: Stem Cell Radiobiology

Chair: Ohtsura Niwa

Established to review current state of knowledge of stem

cell radiobiology and potential impacts on cancer risk.

An increase in knowledge of stem cell biology but little

new information on radiation effects on stem cells.

Emphasis is on stem cell radiobiology in relation to

carcinogenic radiation risk.

Document has been reviewed and approved by the Main

Commission. Currently in press as Publication 131.

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TG 75: Stem Cell Radiobiology

ICRP acknowledges the leadership of

chair O. Niwa, and their hardworking

committee: J.H. Hendry, M.H.Barcellos-

Hoff, R.K. Golbus, J.D., Harrison, P. Jacob,

M.T. Martin, T.M. Seed., J.W. Shay, M.D. Story,

K. Suzuki and S. Yamashita, plus the numerous

consultants, readers and reviewers who all had a

significant impact on this document.

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TG 64: Cancer Risk from Alpha Emitters

Chair: Margot Tirmarche, (France).

Originally this TG was responsible for ICRP

Publication 115. This is now being expanded

to report on potential risks from plutonium,

uranium, thorotrast and radium.

Project delayed due to closure of West Lakes

(UK) awaiting joint analysis of Sellafield and

Mayak workers. Now back on schedule.

The dosimetry contributions of C2 essential

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TG 91: Radiation Risk Inference at Low-dose

and Low-dose Rate Exposure for Radiological

Protection Purposes

Chair: Werner Ruehm (Germany)Members

Tamara Azizova, C1 (Southern Urals)

Simon Bouffler, C1 (UK)

Roy Shore (former C1, Japan/USA)

Gayle Woloschak (USA)

Corresponding members

Bernd Grosche (Germany), Linda Walsh (Germany)

Michiaki Kai, C4 (Japan), Kaz Sakai, C5 (Japan)

Kotaro Ozasa (Japan), Mark Little (USA)

Quanfu Sun, C1 (China)

Consultant

Abel Gonzalez (Argentina)

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TG 91: Radiation Risk Inference at Low-dose

and Low-dose Rate Exposure for

Radiological Protection Purposes

The Task Group will review the estimation of risk

coefficients and recommend:

1. Whether to continue to estimate risk at low doses by

assessing the slope of the dose response at high doses

and then applying a DDREF reduction factor.

1.Whether such coefficients are applicable to acute,

protracted and prolonged exposure or need correction.

1.Separate dose (LDEF) and dose rate (DREF)

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In conjunction with TG 91 there is the Working Group on

Circulatory Disease Detriment

Chair Nobuhiko Ban (Japan)

Goal – determination of circulatory disease detriment.

1.Detriment calculated separately for heart disease and

stroke

1.Analysis of the meta-analysis from the A-bomb

survivors

1.Focus on nominal risk estimates, then adjust for

severity

No formal meetings, teleconferences and conference

meetings.

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Task Group 92: Terminology & Definitions

Chair: Wolfgang Doerr (Austria)

Members

Jai-ki Lee, Main Commission (Korea)

Dominique Laurier, C1 (France)

Frank Wissman, C2 (Germany)

Pedro Ortiz Lopez, C3 (Austria)

Anne Nisbet, C4 (UK)

Almudena Real, C5 (Spain)

Corresponding member

Derek Delves (Austria), Ted Lazo (France)

Cecile Ronckers (Netherlands), Michiya Sasaki (Japan)

Consultant

Abel J. Gonzalez (Argentina)

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Task Group 92: Terminology & Definitions(under the auspices of the Main Commission)

Over many years the terminology and definitions of specific

terms used in ICRP publications have evolved, and in some

instances have been used inconsistently. This Task Group

will review the terminology and definitions from Publication

103 onward and update/revise as required.

1.Definition unequivocal

2. Definition clear, but requires harmonization

3. Definition unclear/missing

4. Definitions conflictive.

It is envisaged that the updated terminology and definitions

will be a web-based resource for future use.

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2016 C1 meeting

Chennai, India. In conjunction with the "International

Conference on Radiation Biology” (ICRB-2016) and “14th

Biennial Meeting of Indian Society for Radiation Biology”.

On or about Nov. 11-13.

Co hosts

Preetha Rajaraman

Mansoor Ahmed & Pat Prassanna (NIH/NCI)